1. Field of the Invention
This invention relates in general to circuit arrangements for the frequency selective analysis of the amplitudes of one or more signals in which a selective receiver automatically passes through a given frequency band and the scanning speed of its frequency spacings is controlled by a value which is dependent upon the difference in amplitudes of adjacent signal voltages received consecutively in time.
2. Description of the Prior Art
There are known circuit arrangements which operate as receivers for scanning a frequency band and measuring with a selective receiver signals received over the frequency band and wherein the time differential of the amplitude changes is determined and used to change the scanning speed of the receiver. However, a disadvantage of such systems exist in that the determination of the time differential requires the processing of information to obtain a control value and the influence of the processing upon the scanning speed requires a rather long length of time during which the signal is analyzed before the frequency scanning speed is changed. Thus, these prior art systems require and include time delay which are undesirable.